I have a wonderful older sister. But lately, she's been the source of my troubles. She may look young, but I'm a man, so I get incredibly excited by women's bodies! So please, sis, don't walk around the house naked after your bath! Will I overcome the premature storm of adolescence with the energy of youth!? A passionate debut manga by the formidable Amatsuki Ruri, depicting everything to the deepest depths. Includes significant revisions and additions, plus a newly drawn bonus chapter!